Patent Application
20070261273
This invention relates to shoes having photoreactive components. More particularly, this invention relates to shoe soles and straps which have photoreactive compositions mixed into the components themselves, so that the components change color when exposed to ultraviolet light.
There have been previous attempts at creating shoes having designs which change from colorless to a particular color, or from one color to another, upon exposure to ultraviolet light. However, these previous attempts essentially consist of attaching photoreactive designs to existing shoes. For example, one such shoe utilizes screen-printing to apply a photoreactive design. Another relies upon the application of a separate photoreactive panel by stitching or an adhesive. There is not, however, a shoe that has components, such as soles and/or straps, that are photoreactive themselves, instead of having photoreactive designs applied thereto.
It therefore would be desirable to provide a shoe that has components which themselves are photoreactive, so that the components change color when exposed to ultraviolet light.
It is therefore an object of the present invention to provide a shoe having photoreactive soles and/or straps that reversibly change color when exposed to ultraviolet light.
It is another object of the present invention to provide a shoe having soles and/or straps that are photoreactive themselves, without a need to apply additional designs or materials to achieve a photoreactive effect.
In accordance with the present invention, a shoe or other article of footwear having photoreactive components is provided. A base material of a sole of the shoe may be plastic, rubber, polymer, or any other suitable material capable of being mixed with a photoreactive composition. The shoe also may have one or more straps, located near a wearer's heel or instep and/or at any other location, also made of any such suitable material.
At least one of a number of different photoreactive compositions may be mixed with the plastic, rubber, polymer, or other base material used to create the sole and/or straps of the shoe. For example, the photoreactive composition may be a spiropyran or spirooxazine composition. The effect of such mixing is that the shoe's sole and/or straps themselves will change color, or become a color if initially transparent, when exposed to ultraviolet light. Additional elements may be mixed with the base material and the photoreactive composition as well, including but not limited to an ultraviolet stabilizer or an antioxidant.
The above and other objects, features, and advantages of the present invention will become apparent upon consideration of the following detailed description, taken in conjunction with the accompanying drawings in which like reference characters refer to like parts throughout.
The present invention is directed to an article of footwear, which may be any type of shoe, sneaker, sandal, boot, or other article worn on a foot. By way of example,
As shown in
Optional strap 40 may be attached to sneaker 1 over or above eyelets 35 to further secure sneaker 1 on a wearer's foot. Strap 40 may be attached above one row of eyelets 35, pass through a loop 45 attached above the other row of eyelets 35, double back on itself, and be secured using a hook-and-loop type fastener as shown; other methods of fastening a strap also may be used. Strap 40 may be made of a base material such as plastic, rubber, polymer, or another material capable of being mixed with a photoreactive composition as discussed below.
At least one of a number of different photoreactive compositions that are known in the art may be mixed with the plastic, rubber, polymer, or other base material to form sole 10 and/or strap 40 of sneaker 1. Among the known photoreactive compositions are a family of molecules known as spiropyrans, or trimethylindolinospirobenzopyran, such as 1′,3′,3′-trimethylspiro [2H-1-benzopyran-2,2′-indoline]. Another group of known photoreactive compositions are spirooxazines, including 1′,3′,3′, trimethylspiroH[2H-1,4-benzoxazine-2,2′-indoline], or BISO; 1′,3′,3′-trimethylspiro [indoline-2′,3′-[3 H]naphtha[2,1-b][1,4]oxazine]; 3-ethyl-9′methoxy-1,3-dimethylspiro[indoline-2,3′-[3 H]naphth-[2,1-b] [1,4]oxazine], or BISO; 1′,3′,3′-trimethylspiro[indoline-2,3′-[3H]pyrido[3,2-f]-[1,4]benzoxazine, or QISO; and oxazilidinospirooxazine.
Each of these molecules changes either from optical transparency to a predefined color, or from one predefined color to another, when exposed to ultraviolet light. When removed from an ultraviolet light source, the molecules return to their original colors.
The base material and the photoreactive composition that make up sole 10 and/or strap 40 may be mixed and then formed using any methods known in the art. For example, the photoreactive composition may be mixed in powdered form into a collection of rubber or polymer pellets, and such mixture then may be injection-molded into the desired shape. There are, of course, numerous methods known for forming plastic, rubber or polymers into shapes such as shoe soles and straps, and any such method may be utilized.
The photoreactive composition may ideally make up between 10% and 90% of the base material-photoreactive composition mixture by weight. Greater amounts of photoreactive composition in the mixture will result in brighter colors being visible upon exposure to ultraviolet light. The photoreactive composition may make up as little as 10% of the mixture by weight; any less and there is a risk that the color change will not be visible. Furthermore, the photoreactive composition may make up as much as 90% of the mixture by weight, but exceeding that amount risks compromising the properties of the base material.
Additionally, other materials may be added to the mixture of the base material and the photoreactive composition, such as ultraviolet stabilizers or antioxidants. These additional materials may serve to increase the amount of time that the photoreactive composition lasts. If used, the ultraviolet stabilizers and/or antioxidants may total up to 10% by weight of the photoreactive composition, or up to 90% by weight of the base material-photoreactive composition mixture.
When sneaker 1 is exposed to ultraviolet light, sole 10 and any optional straps 40 will change from transparent to a predefined color, or from their original color to a new, predefined color. Upon removal of the ultraviolet light source, sole 10 and optional straps 40 will return to their original color or state of transparency.
As above, at least one of a number of different photoreactive compositions that are known in the art may be mixed with the plastic, polymer, or other base material to form sole 110, heel 120 and/or straps 140 of shoe 101, including one of the spiropyrans or spirooxazines families of molecules. The base materials and photoreactive compositions may be mixed and formed as above, using the same proportional limits described in connection with the first embodiment of the invention already described. Additionally, other materials such as ultraviolet stabilizers or antioxidants may be added to the base material-photoreactive composition mixture as described above.
When shoe 101 is exposed to ultraviolet light, sole 110, heel 120, and/or straps 140 will change from transparent to a predefined color, or from their original color to a new, predefined color. Upon removal of the ultraviolet light source, sole 110, heel 120 and/or straps 140 will return to their original color or state of transparency.
Thus, a shoe or other article of footwear having photoreactive elements is provided. Persons skilled in the art will appreciate that the described embodiments are presented for the purpose of illustration rather than limitation and the present invention is limited only by the claims that follow.
